AMERICAN COLEOPTERA. 29 



Amblj'cliila cylindriforinif^, Say. 



Color yellowish white, head and prothoracic scute castaneous. 



Form cylindrical, slightly flattened, head and prothorax bent at 

 right angle to the body, tip of abdomen beyond the larger segment 

 (fifth abdominal), gradually arcuate. Viewed on the dorsal aspect the 

 body is gradually but slightly broader from the metothoracic segment 

 to the fifth ventral, then gradually smaller to the tip which is obtuse. 

 Viewed laterally the body is nearly of equal thickness excepting the 

 gibbosity of the fifth abdominal segment. Length in normal position 

 about 1.25 long, 3.2 mm. or when extended .5 inch, 12.5 mm. longer; 

 thickue^.24 — ..30 inch; 6 — 7.5 mm. The larva before me is probably 

 not fully grown. Plate 11, fig. 1, 1 a to Ig. 



Head corneous, above piceous slightly concave, half covered by the 

 thorax, beneath very convex, resting posteriorly against the anterior 

 coxce. Upper surface of head broader than long, frontal margin tri- 

 lobed, the lateral lobes broadly rounded and covering the base of the 

 mandibles, the middle lobe prominent, obtuse, margin creoate, on each 

 side at base a short obtuse process external to which is an obsolete 

 suture. This lobe con-esponds with the labrum and the suture may 

 be faintly seen entirely surrounding it. Two ridges cross the head 

 transversely, one between the base of the mandibles, the other form- 

 ing the posterior margin of the head, both are feebly tubereulate, the 

 tubercles bearing hairs of varying length. The under side of the 

 head is cordiform in shape, convex, broader than long, with one 

 median suture running from the anterior to the posterior margin, and 

 a short obli(iue impression on each side in front, the two joining on 

 the median line forming a V. The margin of the buccal opening is 

 trilobed, the middle lobe or submentum triangularly emarginate. In 

 the notch separating the submentum from the lateral lobes the maxillae 

 arise. The lateral lobes are longer than the median, their anterior 

 edge has an elevated margin or bead. From the base of the mandibles 

 a curved elevated line extends to the tip of the middle lobe. 



Eyes are situated, one on each side, near the posterior angles of the 

 head on the upper surface and are round convex and simple; surround- 

 ing the eyes are numerous mammiliform tubercles, each bearing a hair. 



Antennae are situated immediately behind the base of the mandi- 

 bles, and are composed of four joints, the first joint stouter, the second 

 nearly twice as long, the third, one-fifth the length of the second and 

 the fourth very minute. The joints have moderately long hairs arising 

 from the upper surface. 



